/*

* bsfilt.c - a colcrt-like processor for cawf(1)

*/

/*

* Copyright (c) 1991 Purdue University Research Foundation,

* West Lafayette, Indiana 47907. All rights reserved.

*

* Written by Victor A. Abell <abe@mace.cc.purdue.edu>, Purdue

* University Computing Center. Not derived from licensed software;

* derived from awf(1) by Henry Spencer of the University of Toronto.

*

* Permission is granted to anyone to use this software for any

* purpose on any computer system, and to alter it and redistribute

* it freely, subject to the following restrictions:

*

* 1. The author is not responsible for any consequences of use of

* this software, even if they arise from flaws in it.

*

* 2. The origin of this software must not be misrepresented, either

* by explicit claim or by omission. Credits must appear in the

* documentation.

*

* 3. Altered versions must be plainly marked as such, and must not

* be misrepresented as being the original software. Credits must

* appear in the documentation.

*

* 4. This notice may not be removed or altered.

*/

#include <stdlib.h>

#include <stdio.h>

#ifdef UNIX

# ifdef USG

#include <string.h>

# else /* not USG */

#include <strings.h>

# endif /* USG */

#else /* not UNIX */

#include <string.h>

#endif /* UNIX */

#include <sys/types.h>

#define MAXLL 2048 /* ridiculous maximum line length */

int Dash = 1; /* underline with dashes */

int Dp = 0; /* dash pending */

int Lc = 0; /* line count */

char *Pname; /* program name */

unsigned char Ulb[MAXLL]; /* underline buffer */

int Ulx = 0; /* underline buffer index */

void Putchar(int ch);

int main(int argc, char *argv[]) {

int ax = 1; /* argument index */

unsigned char c; /* character buffer */

FILE *fs; /* file stream */

int nf = 0; /* number of files processed */

unsigned char pc; /* previous character */

int under = 0; /* underline */

/*

* Save program name.

*/

if ((Pname = strrchr(argv[0], '/')) != NULL)

Pname++;

else if ((Pname = strrchr(argv[0], '\\')) != NULL)

Pname++;

else

Pname = argv[0];

/*

* Process options.

*/

if (argc > 1 && argv[1][0] == '-') {

switch (argv[1][1]) {

/*

* "-U" - underline with dashes.

*/

case 'U':

Dash = 0;

under = 1;

break;

/*

* "-" - do no underlining at all.

*/

case '\0':

Dash = under = 0;

break;

default:

(void) fprintf(stderr,

"%s usage: [-] [-U] [file]\n", Pname);

exit(1);

}

ax++;

}

/*

* Process files. Read standard input if no files names.

*/

while (ax < argc || nf == 0) {

if (ax >= argc)

fs = stdin;

else {

#ifdef UNIX

if ((fs = fopen(argv[ax], "r")) == NULL)

#else

if ((fs = fopen(argv[ax], "rt")) == NULL)

#endif

{

(void) fprintf(stderr, "%s: can't open %s\n",

Pname, argv[ax]);

exit(1);

}

ax++;

}

nf++;

/*

* Read input a character at a time.

*/

for (pc = '\0';;) {

c = (unsigned char)fgetc(fs);

if (feof(fs))

break;

switch(c) {

case '\n':

if (pc)

Putchar((int)pc);

Putchar('\n');

pc = '\0';

break;

case '\b':

if (pc == '_') {

if (under) {

putchar(pc);

putchar('\b');

} else if (Dash)

Dp = 1;

}

pc = '\0';

break;

default:

if (pc)

Putchar((int)pc);

pc = c;

}

}

if (pc) {

Putchar((int)pc);

Putchar((int)'\n');

}

}

exit(0);

}

/*

* Putchar(ch) - put a character with possible underlining

*/

void Putchar(int ch) {

int i; /* temporary index */

if ((unsigned char)ch == '\n') {

/*

* Handle end of line.

*/

putchar('\n');

if (Ulx) {

while (Ulx && Ulb[Ulx-1] == ' ')

Ulx--;

if (Ulx) {

for (i = 0; i < Ulx; i++)

putchar(Ulb[i]);

putchar('\n');

}

}

Dp = Ulx = 0;

Lc++;

return;

}

/*

* Put "normal" character.

*/

putchar((unsigned char)ch);

if (Dash) {

/*

* Handle dash-type underlining.

*/

if (Ulx >= MAXLL) {

(void) fprintf(stderr,

"%s: underline for line %d > %d characters\n",

Pname, Lc, MAXLL);

exit(1);

}

Ulb[Ulx++] = Dp ? '-' : ' ';

Dp = 0;

}

}